Apparatus for molding articles



Nov.'16, 1948. 5. M. MARTIN v 2,454,193

APPARATUS FOR'MOLDING ARTICLES Filed June 13, 1944 2 Sheets-Sheet 1 INVENTOR 5. M MARTIN Armmvsv Nov. 16, 1948. s. M. mam 2,454,193

APPARATUS FOR MOLDING ARTICLES Filed June 13, 1944 I 2 Sheets-shone 37\ e FIG-5 3x 36 INVENTOP ATTORN E Y Patented Nov. 16, 1948 UNITED STAT ES. PATENT OFFICE 2,454,193. APPARATUSFQR MOLDING AR'rroLEs Samuel'M. Martin, Baltimore, Md.', assignor to Western. Electric Company, Incorporated, New York; N. Y., a corporation ofNewv York Application June 13, 1944, Serial No. 540,083

Claims;

This invention relates to apparatus formolding articles, and more particularly to apparatus for molding bodies of insulating material on cords.

In the manufacture of some types of Y-type cords it is necessary to form a body of insulating material around the Y of such a cord. During such molding'operations it is necessary to maintain the conductors of such a cord in a predetermined position in a molding cavity so that the conductors will remain in concentric alignment in the cavity during the molding operation.

An object of the invention is to provide new and improved apparatus for molding articles.

An apparatus embodying the invention comprises a mold having a molding cavity formed therein and means for holding a flexible element of an article to be molded under tension in said molding cavity.

A complete understanding of the invention may be obtained from the following detailed description of a specific embodiment thereof, when read in conjunction with the appended drawings, in which:

Fig. 1 is a top plan view of an apparatus embodying the invention with a portion thereof broken way;

Fig. 2 is a vertical, sectional view of the apparatus taken along line 2-2 ofFig. 1;

Fig. 3 is a vertical, sectional View of the apparatus, similar to Fig. 2 but with the elements of the apparatus in open position;

Fig. 4 is a plan view of an article molded by the apparatus embodying the invention;

Fig. 5 is a bottom plan View of a top die member forming a portion of the apparatus;

Fig. 6 is a top plan view of a frame forming a portion of the apparatus, and

Fig. 7 is a top plan View of a bottom die member forming a portion of the apparatus.

Referrin in more detail to the drawings, a bottom die member I!) (Fig. 3) has a plurality of guide pins H-II secured in lugs l2-l2 projecting from the sides thereof and a plurality of compression springs l5-l5 are mounted on the pins i !l I. The die member ID has a molding recess [3 (Fig. '7) formed longitudinally thereof and a plurality of overflow passages ll-il extending along the sides of the recess 16. The overflow passages il-ll'are separated from the recess It by thin ridges l8-l8 formed therebetween.

A frame 20 (Fig. 6) having a plurality of bores 21-2 lformed therein is designed to be slid-abl}, mounted-on the pins ll-ll with the pins projecting through the bores 21-21 Arectangular opening 22 formed in the frame 220* is slightlyaction of the springs Iii-l5, as shown in Fig. 2.

A clamping plate 25 (Fig. 6) is mounted above one end of the frame on a pair of bolts 26-26 projecting from the frame Zil. A pair of wing nuts 21-21 serve tosecure' the clamping plate on the bolts 26-25; A similar clamping plate 30 is secured by a wing nut 32; upon a bolt 3| projecting from the upper surface of the frame 20'.

An upper die member 35 (Fig. 5) is provided witha plurality of lugs 36-36 projecting therefrom. The lugs 36-36 have bores 31-31 formed therein which are so positioned that the guide pins l l-Il enter the bores 31-31 when the die member 35 is positioned over the bottom die member Ill; as-shown in Fig 2. The lugs 36-36 are equal in height to the body portion of the die member 35and, when the die member 35 is placed in the position shown in Fig. 2 of the drawings, serve to press the frame 28 below the upper surfaceof the body portion of the die member [0 against the action of the compression springsl5-l5.

A molding recess (Fig. 5) formed in the die member "35 cooperates with the molding recess [3, when the die members Ill and 35 are in the positions shown in Fig. 2, to form a molding cavity.

A' plurality of overflow passages 4l-4l formed in the die member 35 are separated from the recess 40' by ridges 42-42. When the die members IO- and 35 are placed under pressure and assume the positions shown in Fig. 2, the ridges l'8-I8 and 42-42 are placed in abutting rela-- tionship and the passages ll-l'l and 4l-4l 00-- act to form overflow passages.

In the operation of the apparatus described hereinabove to form a built-upbody of insulating material such as a body 45' (Fig. 4) of a Y-- type cord 48 from a plurality of rubber strips 41-41 (Fig. 6) the strips 41-41 are wrapped around the crotch of a Y formed by a pair of rubber jacketed, individually insulated, two-conductor cords 48-48 and a pair of individually in sulated conductors 49-49 and a stay cord 58 Each of the conductors 49-49 forms a portion of one of the cords 48-48. The clamping plate 25 then is forcedby the wing nuts 21-21 against the cords 48-48 ofthe cord 46 to secure the cords 48-48 against the frame 28 in positions shown in Fig. 6 of the drawings.

The ends of the conductors 49-49 and the stay cord '50 then are placed between the clamping plate 30 and the frame 20, are drawn taut, and the wing nut 32 is actuated to clamp the conductors 49-49 and the stay cord 50- against the frame 20. The clamping plate 30 (Fig. 6) serves to secure the conductors 49-49 and the stay cord 59 against the frame 20 with the wrapped portions of the conductors 49-49, the stay cord 50 and the cords 48-48 extending between the clamping plates 25 and 35 and under tension.

The frame 26 with the elements of the cord 46 secured thereto is then placed over the bottom die member ID and is slid over the guide pins H-l I. When the frame 20 and the elements of the cord 46 held thereby are in this position, the elements of the cord 46 are positioned directly over the recess IS. The upper die member 35 is then slid over the guide pins ll-ll with the pins lI-H extending into the bores 31-31 thereof. The assembled mold is then placed in a molding press (not shown) of a conventional type and the press serves to force the die members l and 35 together and the frame 20 over the upper portion of the die member ID, as shown in Fig. 2. When the plate 20 is pressed downwardly to the position shown in Fig. 2, the elements of the cord 46 are held concentrically with respect to the molding cavity formed by the recesses I6 and 40.

At this time portions of the conductors 49-49, the stay cord 50 and the cords 48-48 between the plates 25 and 30 are held in axial alignment with the molding cavity formed by the molding recesses I6 and 40, and since they are held under tension by the clamping plates 25 and 30, the pressure upon the rubber strips 41-41 cannot dislodge the conductors 49-49, the stay cord 50 and the cords 48-48 as the body 45 is formed concentrically on the other elements of the cord 46 from the strips 41-41. Any of the rubber composition embodied in the strips 41-41 which is in excess of the amount of that material required to form the body 45 will be forced into the overifow passages l1-l1 and 4l-4l.

The elements of the apparatus thenare held in the positions shown in Fig. 2 of the drawings and are heated by the conventional heating means until the strips 41-41 are set in the form of the body 45, after which the die members l0 and 35 are withdrawn from the molding press and the die member 35 is moved away from the bottom die member l0 by the actions of the springs [-15. As the die member 35 is slid upwardly on the pins Il-ll, the compression springs l 5-15 force the frame 20 upwardly, as viewed in Fig. 2, whereby the cord 46 is raised from the recess 16. The die member 35 then is removed completely from the pins l l-l I and the wing nuts 21-21 and 32 are loosened to release the cord 46 from the clamping plates 25 and 30. Another cord similar'to the cord 46 then may be formed in a manner similar to the one just described.

As the frame 20 is pushed downwardly during a molding operation similar to that described above, the elements of the cord 46 secured to the frame are maintained under tension between the ends of the frame and are carried in a plane just above the frame 20. Thus, these elements of the cord 46 are prevented from sagging or being forced out of alignment with the molding cavity when the parts to be molded are subjected to pressure, whereby the cord 46 is perfectly formed.

A frame and elements associated therewith identical with the frame 20 and the elements associated therewtih may be used equally as Well with a mold of the type which is designed to have molding material injected into the molding cavity thereof as the frame 20 is used with the die members I!) and 35. The operation of the lastdescribed apparatus is identical with that described hereinabove except that the insulating material to be molded is injected into the closed mold rather than being in the form of the strips 49-49.

What is claimed is:

1. A molding apparatus, which comprises a pair of die members having complementary molding recesses formed therein and relatively movable from an open relationship to a molding relationship, means for aligning the die members, a rigid loading frame floatingly mounted with respect to the die members, said frame being removable from the die members, and clamping means mounted on the ends of the frame for securing a flexible core of a cord to the frame.

2. A molding apparatus, which comprises a stationary die member having a main body portion provided with a molding recess formed therein, a movable die member having a main body portion provided with a molding recess formed therein complementary to the first-mentioned recess, said second die member being movable from an open position into molding relationship with the stationary die member to form an article molding cavity therebetween and also being provided with lugs projecting from the main body portion thereof, a removable frame having an opening between the ends thereof for clearing the stationary die member, clamps carried on the ends of the frame for securing a flexible core of a cord to the frame in a taut condition, and means for urging the frame against the lugs of the movable die member when the molds are in a molding relationship.

3. A molding apparatus, which comprises a stationary die member having a molding recess formed therein, a plurality of guide pins, a movable die member having a molding recess formed therein complementary to said first-mentioned molding recess and being slidably mounted on the guide pins so that the second die member can be moved from an open position into molding relationship with respect to the stationary die member, a frame mounted slidably and removably on the guide pins, resilient means for urging the frame against the movable die member when the die members are in a molding relationship, and clamps positioned on the ends of the frame for securing a flexible core of a cord to the frame under tension, whereby the core is held in a predetermined relationship with respect to the molding recesses when the die members are positioned in molding relationship.

4. A molding apparatus, which comprises a lower, stationary die member having a molding recess formed in the upper face thereof, a plurality of guide pins, a loading frame slidably and removably mounted on the guide pins and having an opening therein which permits the frame to fit over said die member, a pair of clamps mounted on one end of the frame for securing two arms of a core of a Y-type cord to that end of the frame, a clamp mounted on the other end of the frame for clamping the stem of the core of the cord to that end of the frame, said clamps coacting to secure the portions of the core between the ends of the frame under tension, an upper die member having a molding recess formed in the lower face thereof complementary to said first-mentioned molding recess, said upper die member being slidably and removably mounted on the guide pins for pressing the guide frame over the stationary die member and being movable int-o molding relationship With said stationary die member, and a plurality of springs positioned over the guide pins for yieldingly supporting the frame.

5. A molding apparatus, which comprises a stationary die member having a Y-shaped molding recess formed therein, a plurality of guide pins projecting from the stationary die member, a loading frame slidably and. removably mounted on the guide pins and having formed therein an opening for providing clearance for the portion of the stationary die member having the recess therein, a pair of clamping plates mounted on one end of the frame in spaced positions for clamping arms of a flexible core of a Y-type cord to that end of the frame, a clamping plate mounted on the other end of the frame for clamping the stem of the core to that end of the frame after the arms and the stem of the core have been tensioned, a movable die member having formed therein a Y- shaped molding recess complementary to the rel 6 cess in the stationary die member and slidably and removably mounted on the guide pins for pressing the loading frame toward the stationary die member, and a plurality of compression springs mounted on the guide pins for pressing the loading frame against the movable die member when the I die members are in a molding relationship.

SAMUEL M. IMARTIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

